How do Solar Panels Work and Solar Power Plant Work?

Solar panels work by converting sunlight into electricity. This is done using a process called the photovoltaic effect. The photovoltaic effect is a physical phenomenon in which light energy is converted into electrical energy. When sunlight hits the semiconductor on a solar cell, it creates an electric field. This electric field separates the positive and negative charges in the semiconductor, creating a voltage. This electric charge flows through the solar panel and produces electricity. Each solar cell generates a voltage (~.5 V) regardless of size, according to Portland State University.

The solar panel converts the sunlight falling on it into voltage differences. The potential difference causes a direct electric current (DC) to pass through the solar cells. Then, an inverter in the solar system converts the direct current and alternating current (AC), making it usable in homes and businesses.

Solar panels work and convert the sunlight into electricity through several steps (Absorption of solar energy, generation of electrons, creation of electric field, flow of electrons, and more)

Solar Modules’ absorption of solar energy depends on their exposure to sunlight, day’s hour count, seasons and climate, and solar angles. For example, The University of Queensland study has found that the maximum sunlight intensity on a bright summer day is around 1400 W/m2, while it is less than 50%, this affects the photovoltaic cells’ workability and efficiency. When solar panels absorb solar energy, some of solar power is transformed into heat.

A solar plant works to harness the energy from the sun to generate electricity through a process called concentrated solar power, while a solar farm directly generates electricity by employing solar panels composed of photovoltaic cells.

This article discusses:  What Solar Panels Do? How do solar panels generate electricity from solar energy? When do Solar Panels Work? Do solar panels work at night, in indirect light, in winter, in cloudy weather? How do Solar Power Plant Systems Work? What is the Difference Between Solar Farms and Solar Power Plants? Do solar panels generate heat? 

The following figure illustrates how solar panels work 

What Do Solar Panels Do?

Solar panels generate electricity through the photovoltaic effect process which has 8 steps are:

• Absorption of solar energy
• Generation of electrons
• Creation of electric field
• Flow of electrons
• Collection of eurrent
• Conversion to usable voltage and current
• Inversion of the current
• Getting usable electricity 

Solar panels depend entirely on solar energy to generate electricity. Solar panels convert sunlight, a form of solar energy, into electrical energy through the photovoltaic effect. This means that solar panels cannot work and produce electricity without access to sunlight.

Solar panels’ workability depends on sunlight whether it is direct, indirect, or even absent such as at night. The panels’ ability to work also varies in winter and cloudy weather.

How Does a Solar Panel Work?

A solar panel work when sunlight hits a it. The PV cells in the panel absorb the energy. This absorption generates an electrical charges that respond to an internal electrical field within the panel, leading to the flow of electricity.

Solar panels generate electricity from solar energy through a process known as the photovoltaic effect, “which is a physical and chemical phenomenon”(Schroder, D. K. (2015)). The photovoltaic effect involves converting solar energy directly into electricity using semiconductor materials. 

“The solar radiation of visible range from 0.38 µm to 0.72 µm is mainly used for electricity generation by photovoltaic energy conversion process”, according to “Thermodynamics of Photovoltaic and Concentrator Photovoltaic Systems and Determination of Their Energy and Exergy Efficiencies” research by Dr. Rahul Rawat.

Solar panels 8 working steps are in this figure. 

The following list shows how are solar panels work step by step.

1. Absorption of solar energy. Solar panels comprise many individual solar cells. Solar cells are composed of silicon or other semiconductor materials. These cells absorb photons (particles of light) from the solar energy (Solar radiation). 

2. Generation of Electrons. An electron is a subatomic particle with a negative electric charge. When photons, the fundamental particles of light from sunlight, strike the solar cell’s surface, they transfer their energy to electrons in the semiconductor material. This energy excites the electrons, allowing them to break free from their normal positions within the atoms of the material and create what are known as electron-hole pairs.

3. Creation of Electric Field. The semiconductor material in solar cells works to create an electric field within the material. This electric field helps to separate the newly freed electrons from the positively charged “holes” they left behind.

4. Flowing of Electrons: Due to the electric field, the free electrons are pushed to one side of the solar cell, while the holes are made to the other side. This work of separation of charges creates a voltage difference between the two sides, resulting in an electric current.

5. Collection of Current. Conductive metal contacts on the top and bottom of the solar cell allow the generated electric current to flow out of the cell and into an external circuit.

6. Conversion to Usable Voltage and Current. The raw electricity generated by a single solar cell is relatively small. Many solar cells are connected in series and parallel to form a solar panel to make it practical for powering devices or feeding into the electrical grid. This arrangement works to increase the voltage and current output to usable levels.

7. Inversion of the current. If the intention is to use solar-generated electricity in a regular household or grid-connected setup, the direct current (DC) produced by the solar panels must be converted into alternating current (AC). The alternating current (AC) is the standard form of electricity used in homes and businesses. This inversion process is done using an inverter.

8. Getting Usable Electricity. The converted AC electricity work to power homes, appliances, lights, machines, and other electrical devices, either directly within a building or by feeding excess electricity back into the grid.

When do Solar Panels Work?

Solar panels work whenever they are exposed to sunlight, typically during daylight hours in all seasons, even in winter. They are most productive when the sun shines directly on them (at noon). Solar panels typically generate the most electricity between 10am and 4pm. Solar panels make electricity even in low-light conditions, such as dawn and dusk, according to the National Renewable Energy Laboratory (NREL). The exact timing vary depending on location, the season, and local weather conditions.

The following parts answer the following question: Do Solar panels work at night? Do solar panels need direct sunlight to work? Do solar panels work in winter? Do solar panels work in cloudy weather?

This picture shows solar panels’ 4 work conditions.

Do Solar Panels Work at Night ?

No, solar panels do not work at night due to the absence of sunlight. However, energy storage systems like batteries are used to provide electricity during nighttime hours, and grid-connected systems also help ensure a continuous power supply.

Solar panels do not work in the dark because they need the sun’s power to produce electricity. Solar panels make electricity through the photovoltaic effect, which involves the conversion of sunlight into electric current. When the sun is not shining, such as during nighttime, no sunlight is available to create the necessary energy to produce electricity.

Do Solar Panels Need Direct Sunlight ?

No, Solar cells work even without direct sunlight. Solar panels work in (Direct Sunlight and indirect Light). Solar panels’ work efficiency is significantly higher by 30% to 50%  when they receive direct sunlight, according to the National Renewable Energy Laboratory (NREL). 

Do Solar Panels Work in Winter?

Yes, Solar panels work in winter, but they produce 20% -25% less electricity than in other seasons, particularly in regions with cold climates and shorter daylight hours, according to the National Renewable Energy Laboratory (NREL). The University of Queensland study has found that the maximum sunlight intensity on a bright summer day is around 1400 W/m2, while it is less than 50%, this affects the solar panels’ workability and efficiency. In winter, Solar panel production depends on daylight hours, sun angle, snow cover, and temperature.

To obtain the highest efficiency in generating electricity during the winter, solar panels are installed at certain angles. Solar panel angles play a crucial role in electricity production, especially in winter, according to research by The Northern Alberta Institute of Technology. The best solar panel angle in winter is 45 degrees, according to The Northern Alberta Institute of Technology.

Do Solar Panels Work in Cloudy Weather?

Yes, solar panels work in cloudy weather, although their work efficiency decreases by 10%- 25% compared to sunny conditions. Solar panels absorb direct sunlight and diffuse sunlight. Diffuse light is the scattered sunlight that passes through clouds. A solar pane, in the United States, produce an average of 15% less electricity on cloudy days than on sunny days, according to a 2018 study by The National Renewable Energy Laboratory.

How do Solar Power Plant Work?

A solar plant (solar power plant) or solar (thermal power plant) harnesses the energy from the sun to generate electricity through a process called concentrated solar power (CSP). 

The following list contains the 4 steps of solar plants’ work.

• Solar plants use an array of mirrors or lenses to focus sunlight onto a central point or receiver. 
• The concentrated sunlight heats the receiver’s specialized heat-transfer fluid, molten salt. 
• The heat generated by the concentrated sunlight causes the fluid to reach high temperatures. This hot fluid then produces steam by transferring its heat to water.
• The steam generated in the previous step is used to drive a turbine. The turbine, connected to an electric generator, converts the kinetic energy of the spinning turbine into electrical energy, producing electricity.

There are differences between a solar plant and a solar farm in their way of work. And, the size of the utility that a solar plant and a solar caters to.

What is the Difference Between Solar Power Plants and Solar Farms?

A solar plant ( solar power plant) or solar thermal power plant work through the ingenious application of mirrors or lenses to focus sunlight onto a receptor. This receptor heats a fluid, inducing the formation of steam that propels a turbine, thus creating electrical energy. This innovation is recognized as concentrated solar power (CSP) and is predominantly harnessed for expansive utility ventures. A solar power plant consists of solar panels as a fundamental component.

In contrast, a solar farm works to generate electricity by employing solar panels composed of photovoltaic cells. These cells convert sunlight into electrical energy, a process known as solar photovoltaic (PV) technology. This method is commonly employed for more compact undertakings, such as residential and commercial installations.

To conclude, the key difference between a solar plant and a solar farm is in their work the methods to electricity generation. Solar plants utilize concentrated solar power, whereas solar farms employ photovoltaic cells to instantly convert sunlight into electrical energy. Additionally, solar plants are predominantly geared towards sizable utility initiatives, whereas solar farms cater to smaller-scale ventures.

What is Solar Panels Efficiency?

Solar panel efficiency is how solar panels’ work well in converting sunlight into electrical energy. Solar panel efficiency is the ratio of electrical output to the amount of sunlight that strikes the surface of the panel.

Do Solar Panels Generate Heat?

Yes, solar panels generate heat. When solar panels work, the cells absorb the energy from the sunlight, during this process, some of the power from the sunlight is transformed into heat. However, this heat is produced in small quantities that are not sufficient for home use, so solar thermal is usually used to generate sufficient heat for homes. 

Thermal panels (solar thermal panels or solar collectors) are devices that work to collect heat from the sun and use it to heat water or other fluids.